Please try with the picture.

I hope these pictures help. One is on my tomatoes and the other on the pepper's and now they are on my zucchini.

Not really clear, but I'd guess aphids.

They are white flies, I think.
Aphids and white flies are similar in size. White flies are jumpy. Aphids live on the leaves rather than under them. I have never seen them to infest tomatoes.

"Aphids live on the leaves rather than under them. I have never seen them to infest tomatoes."

Most aphids' entire life cycle is lived out on the underside of leaves.
They most certainly do infest tomato plants.

Hard to tell from your out of focus pic, but I'm guessing aphids.
Adult whiteflies would have flown off as soon as you turned those leaves over.

There are many discussions here on GW dealing with aphid problems. Just do some searching and you'll find loads of info.

This post was edited by robeb on Thu, Aug 15, 13 at 1:27

Thanks everyone.I have read about aphid's and haven't found any that are white and all are decribed as being bigger than what I got. They do fly when you get near them and they are mostly under the leaves. I guess I'll take some to a garden supply and see if they can help. I"m thinking about trying to dust them with seven,what do you think ???